Question

There are 87,45,154 children in a city. Out of this 45,17,982 are boys. How many girls are there in the city?

• A. 42,27,172
• B. 41,27,174
• C. 42,72,182
• D. 44,28,352

Answer 1

The correct option is A 42,27,172

Number of children in the city = 87,45,154
Number of boys = 45,17,982

Number of girls = 87,45,154 - 45,17,982
= 42,27,172

Alternative trick solution,
The digit at ones place in 87,45,154 is 4
The digit at ones place in 45,17,982 is 2
Difference of ones place = 4 - 2 = 2

The digit at tens place in 87,45,154 is 5
The digit at tens place in 45,17,982 is 8
When we subtract 8 from 5 after borrowing from hundreds digit,
15 - 8 = 7
we get 7 at the tens place in the answer.
Only,
So, only option C has 7 at tens place and 2 at ones place.